[pe.cust.bugs] P-E and float?

joe@petsd.UUCP (Joe Orost) (03/22/85)

I wanted to share this response with you all.  If you can provide more input
for this guy, please send him email (..!ucbvax!hugh@BRL-BMD.ARPA).

In article <9195@brl-tgr.ARPA> you write:
>	We have been given access to a Perkin-Elmer running the
>Wollogong(sp?) implementation of unix and have found that the simplest
>versions of programs written in both FORTRAN and C don't work.  
>I think that I have isolated the problem:  my conclusion is that
>this implementation doesn't have{_ float in C and doesn't have
>REAL in FORTRAN.  When I declare my variables as double or DOUBLE
>PRECISION in C or FORTRAN, respectively, the programs work; declared
>as float or REAL, they don't work.
>
>	Is this standard for this implemetation?  Or should I tell
>the system administrator to get to work straightening out this problem?

We too had this problem a long time ago.  I think it turned out to be a C
compiler bug.  I think this was fixed right after unix was brought up on our
machine (before it was released as EDITION VII), but like I said this was a
long time ago.

I suggest you get a copy of the latest version of EDITION VII from
Perkin-Elmer.  This is basically the Wollengong port with lots of bugs fixed
(V7 unix).  Or you can order XELOS if you want a port of System Vr2.

					regards,
					joe

--
Full-Name:  Joseph M. Orost
UUCP:       ..!{decvax,ucbvax,ihnp4}!vax135!petsd!joe
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jer@peora.UUCP (J. Eric Roskos) (03/22/85)

This article mentioned the "Wollongong" version ... having worked with the
original Wollongong version extensively, I know that indeed floating point
types in general do not work right in the version released by the
University of Wollongong. (I think PE fixed them.) The problems center
around the fact that the version he used when he ported the compiler only
supported one size of floating point word; there are all kinds of problems
related to floating point word length (e.g., constants are generated with
the wrong word length, activation records are created with the wrong size
(assuming a shorter word length than is actually used), etc.).  We tried to
fix that back when I was at Vanderbilt, and finally gave up because the
problems were so widespread (one of the people in our department had
programs for doing Hartree-Fock computations on atomic orbitals that would
reveal bugs in almost every FORTRAN compiler around, and she found new ones
as fast as we fixed the old ones).  We wrote to S.  I.  Feldman (the
Fortran compiler author) about the problems, and found out that in fact the
version of the Fortran compiler the U. of Wollongong people used was way
out of date at the time they released it (because there were also some
parser problems which Feldman said he'd fixed "several years ago").  Again,
I believe those problems don't exist in PE's released version.

I'll leave it to the compiler people at PE to comment on the current version,
but yes, if he's using the original Wollongong version, there are extensive
problems with floating point...
-- 
Full-Name:  J. Eric Roskos
UUCP:       ..!{decvax,ucbvax,ihnp4}!vax135!petsd!peora!jer
US Mail:    MS 795; Perkin-Elmer SDC;
	    2486 Sand Lake Road, Orlando, FL 32809-7642

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